Effective clinical and translational research requires rigorous study designs, appropriate application of analytic methods, and careful reporting. The Biostatistics, Epidemiology, and Research Design (BERD) has been instrumental in expanding clinical and translational research of new investigators, community partners, and programs of the OSCTR, supporting over 470 research projects, resulting in 72 peer-reviewed publications and 112 grant applications (78 extramural and 34 intramural applications). The BERD has enhanced research methods training (130 seminars/lectures, supporting 25 MS in Clinical and Translational Science thesis projects), expanded the use of novel analytic methods and research designs (31 publications, 48 seminars, five workshops, and two grant-funded projects), and expanded research infrastructure through the deployment of a survey calling center and enhanced REDCap infrastructure, growing use from 6 projects/year to 207 projects in 2016. The revised mission of the BERD Core is to enable OSCTR investigators and partner institutions to design, perform, and report rigorous, reproducible, and innovative studies that can be applied to improve clinical care and patient well-being in Oklahoma and other IDeA states. To do this, the BERD Core provides consultative expertise in biostatistics, epidemiology, and qualitative research methods (Aim 1); coordinates a new, unique and robust data repository infrastructure and analytic skill set for clinical epidemiologic studies (Aim 2); and develops and applies novel research designs and analytic methods focused on the needs of OSCTR research (Aim 3). BERD Core members collaborate with investigators to address sources of bias, identify sufficient sample sizes, select measurement instruments, perform data quality control, manage and analyze data, and report study results. The BERD Core works with the Professional Development Core to develop workshops on research methods, and with the Administrative Core to produce training videos, templates, and fact sheets for the portal. A new BERD initiative with this renewal, the Clinical Data Warehouse, leverages a unique resource developed at OUHSC to make de-identified electronic medical records available for research to enhance the capacity for clinical epidemiologic and population health research in Oklahoma. The BERD Core helps investigators identify appropriate data sources and variables to address their research questions, then uses the Clinical Data Warehouse validated process to generate a project dataset. Finally, to advance biostatistics and epidemiologic methods, the BERD Core holds monthly seminars to disseminate novel research designs, analysis methods, and research findings. The BERD Core performs methodological research to adapt existing methods or develop new approaches to address research questions, for example, developing new statistical methods to reduce bias and increase estimation efficiency in small populations, such as American Indian tribes. Together, these activities of the BERD Core enable OSCTR investigators to perform rigorous, reproducible, and innovative research to better understand and address health needs in Oklahoma.